The Oscar winner wanted to show her support to the LGBT community following the landmark Supreme Court decision a few weeks ago to legalize gay marriage, so she had a trick up her sleeve!

She works with both W Hotels (the wedding took place at the W Dallas – Victory), and the human rights campaign for marriage equality called Turn It Up For Change.

And she surprised the heck out of everyone. Take a look at this video, and try to be just as surprised as the grooms! Tune into the 1:30 mark to watch the magic happen.

Believe it or not, no one at the wedding had any idea the Dreamgirls star would make an appearance.

"The crowd went wild -- none of them knew about the surprise," a source told Page Six. "The grooms were completely shocked -- it took them a minute to recover from the initial shock and dance along with Jennifer."